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Thread: pg.conf re-reading in signal handler or at next return to main loop?

pg.conf re-reading in signal handler or at next return to main loop?

From
"Markus Bertheau"
Date:
Hi,

src/backend/utils/misc/README says

"
If SIGHUP is received, the GUC code rereads the postgresql.conf
configuration file (this does not happen in the signal handler, but at
next return to main loop; note that it can be executed while within a
transaction).
"

SIGHUP_handler() calls ProcessConfigFile() which calls
ParseConfigFile() which reads postgresql.conf.

For me that means that postgresql.conf in read in the signal handler,
which contradicts the claim in the README. Where's my error?

Markus Bertheau

Re: pg.conf re-reading in signal handler or at next return to main loop?

From
Tom Lane
Date:
"Markus Bertheau" <mbertheau.pg@googlemail.com> writes:
> SIGHUP_handler() calls ProcessConfigFile() which calls
> ParseConfigFile() which reads postgresql.conf.

> For me that means that postgresql.conf in read in the signal handler,
> which contradicts the claim in the README. Where's my error?

The comment is referring to the control flow in a backend; you're
looking at the postmaster's sighup handler, which is different.
        regards, tom lane

Re: pg.conf re-reading in signal handler or at next return to main loop?

From
"Markus Bertheau"
Date:
2006/3/6, Tom Lane <tgl@sss.pgh.pa.us>:
>
> The comment is referring to the control flow in a backend; you're
> looking at the postmaster's sighup handler, which is different.

Then the following comment patch is appropriate, afaics.

Markus Bertheau
Attachment

Re: pg.conf re-reading in signal handler or at next return

From
Bruce Momjian
Date:
Code comment patch applied.  Thanks.

---------------------------------------------------------------------------

Markus Bertheau wrote:
> 2006/3/6, Tom Lane <tgl@sss.pgh.pa.us>:
> >
> > The comment is referring to the control flow in a backend; you're
> > looking at the postmaster's sighup handler, which is different.
> 
> Then the following comment patch is appropriate, afaics.
> 
> Markus Bertheau

[ Attachment, skipping... ]

> 
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--  Bruce Momjian   http://candle.pha.pa.us SRA OSS, Inc.   http://www.sraoss.com
 + If your life is a hard drive, Christ can be your backup. +

Re: pg.conf re-reading in signal handler or at next return to main loop?

From
Tom Lane
Date:
Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Code comment patch applied.  Thanks.

The comment was in fact correct as it stood, though in different ways
for the postmaster and backend --- in the postmaster it alludes to the
fact that we only enable signals at one point in the postmaster loop.
        regards, tom lane

Re: pg.conf re-reading in signal handler or at next return

From
Bruce Momjian
Date:
Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Code comment patch applied.  Thanks.
> 
> The comment was in fact correct as it stood, though in different ways
> for the postmaster and backend --- in the postmaster it alludes to the
> fact that we only enable signals at one point in the postmaster loop.

OK, patch backed out.

--  Bruce Momjian   http://candle.pha.pa.us SRA OSS, Inc.   http://www.sraoss.com
 + If your life is a hard drive, Christ can be your backup. +